Last year I sold a property and used the funds to purchase a set of 3 land loans in the name of the partnership, which have been paying mostly interest and a little principal on a monthly basis.

Currently, the principal, interest, taxes, and insurance (PITI) amount to $3,329 monthly.

Or is it okay to work for a private one/two man shop- where Im friends with the principal and who has all the knowledge and experience from working for the big firms...

The basis could be the price their sister in law sold her house for 3,000 miles away; the amount of principal, interest, taxes, insurance, and repairs they put in (known as “make me whole”), an amount that makes clear they are not to be trifled with (“I won’t give it away!”)

There are a lot of details you haven't filled in in this post (which is fine), but you will likely need a key principal to co-sign loan and a contract with an experienced property management company.The key principle will co-sign the loan to help show the net worth and liquidity needed for the underwriting department.  

More details:Mortgage (principal + interest): $2930/moProperty taxes: $15K/yearHome insurance: ~$1K/yrCost of home ownership/month: $4280/yr (not counting for any tax deductions related to the interest and property tax)If I account for $20K of interest and $10K of property taxes as an income deduction, then I can reduce the cost by ($30K x 35%) divided by 12 = $875 per month = $3400/mo cost of owning the houseRental income after 35% federal income tax + 9.3% state income tax = $2618/month (!!)

The reason most brokerages arnt into this is because if 25% of your transactions are you as a principal or representing family members, then most e&o policies will not cover you. 

If you have an opportunity that peaks their interest and fits within their mandate you may get an audience with the principal but you will have to go through some serious vetting and due diligence first. 

Average well over 20% in IRR due to principal pay down.I don't carry the debt or the risk.

$ for PITI (Principal, Interest, Taxes, Insurance); • 10% for Management; (even if self-managing, pay yourself for your time)• 5-8% for Vacancies; (Turnover happens & when it does it requires cleanup, repairs, listing, showing & leasing which can take up to a month easily.)• 5% for Repairs & Maint; (Repairs happen even on new builds)• 5% for CapEx; (Larger Expenditures will happen over time, so you have to figure for them.)• ?